The sonic "Shimmer Effect" was developed by The Edge of U2 with producer Brian Eno during The Unforgettable Fire recording sessions. Informally dubbed "the shimmer," it involves splitting the guitar's signal and sending one output to the usual effect/amp chain while simultaneously routing the other through a harmonizer and reverb unit. On "Shimmerlicious", Tom utilizes a plug-in designed to replicate the effect, ValhallaShimmer.

Shimmerlicious • The sonic "Shimmer Effect" was developed by "The Edge" of U2 with producer Brian Eno during The Unforgettable Fire recording sessions. Informally dubbed "the shimmer," it involves splitting the guitar's signal and sending one output to the usual effect/amp chain while simultaneously routing the other through a harmonizer and reverb unit. The harmonizer is set to replicate the guitar signal at ascending octave intervals, while heavy reverb provides an atmospheric vibe. The result is an angelic, orchestral sound that shadows the main guitar signal, giving it an almost otherworldly presence. On "Shimmerlicious", Tom utilizes a plug-in designed to replicate the effect, ValhallaShimmer. This is "all effect" similar to what "The Edge" uses on the intro to Where the Streets Have No Name, most people assume it's a synthesizer, but it is actually a very heavily effected guitar signal.